The problems of adequately sealing coke oven doors are well known and highly publicized. Coke oven doors are necessarily located in harsh and demanding environments. They are subject to extremes of temperature and to virtually unavoidable abuse as they are removed and relocated during the continuous cycles of coke making. Many types of doors and seals therefor have been tried through the years in attempts to contain the noxious coke oven gas and to prevent the buildup of deposits therefrom around the periphery of the seal. Deposits from the coke oven gas tend to harden, complicating the problems of obtaining adequate sealing.
As a rule, the atmospheric pressure within the heated coke oven during the coke making process is considerably higher than pressures immediately outside. The pressure drop in the area of a leak, therefore, contributes significantly to the tendency of materials in the coke oven gas to form deposits in the immediate area of the leak, which generally will be in the seal area. Where such deposits are formed, they will render it even more difficult to obtain a good seal on succeeding cycles. It is desirable, therefore, to reduce the pressure drop across leaks in the seal, in order to minimize undesirable depositions from escaping gas.
It is also desirable to reduce significantly the difference in pressure across any leaks in the seal in order to reduce the volume of noxious gas liable to escape, since the flow rate of gas will tend to increase exponentially with the pressure difference.
The reader may be interested in reviewing U.S. Pat. No. 2,275,400 which employs vertical gas channels at the sides of the plug, and U.S. Pat. No. 2,855,347, which includes a central gas channel having feeder ducts inclined upwardly from communication with the oven. Neither of these disclosures, however, accomplishes a decrease in pressure over substantially the entire both sides of the door.